Image display device

ABSTRACT

An image display device includes an image display unit including a display panel, a shelf board, and an illumination unit. The display panel is switchable between an image display mode in which an image is displayed and a transmissive mode in which the display panel is in a transmissive state where objects behind image display unit is visible in a front view of the display panel. The shelf board is disposed projecting rearward from the rear surface of image display unit, and extends in the lateral direction. The illumination unit is disposed above the shelf board and emits light downward.

TECHNICAL FIELD

The present disclosure relates to an image display device which includesa display panel operable in a transmissive mode.

BACKGROUND ART

Patent Literature (PTL) 1 discloses a display device which includes atransparent display. The display device includes: a first panel whichperforms display with use of transparent organic light-emitting diode(OLED) elements; a second panel which includes polymer-dispersed liquidcrystals, is disposed on the rear surface of the first panel, andshields or transmits light from the back; and a controller whichswitches the second panel between a transparent state and an opaquestate. The display device makes the second panel transparent, so that animage of each object behind the first panel and an image on the firstpanel can be simultaneously viewed. Moreover, it is possible to displaya clear image with a high contrast with no intervention of outdoor lightfrom the back of the first panel by making the second panel opaque.

CITATION LIST Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No.2013-156635

SUMMARY OF THE INVENTION Technical Problem

The present disclosure provides an image display device which is capableof effectively using a display panel operable in a transmissive mode.

Solution to Problem

An image display device according to the present disclosure includes: animage display unit which includes a display panel switchable between animage display mode and a transmissive mode, the image display mode beinga mode in which an image is displayed, the transmissive mode being amode in which the display panel is in a transmissive state where anobject behind the image display unit is visible in a front view of thedisplay panel; a shelf board which is disposed projecting rearward froma rear surface of the image display unit, the shelf board extending in alateral direction; and an illumination unit which is disposed above theshelf board and emits light downward.

Advantageous Effect of Invention

An image display device according to the present disclosure is capableof effectively using a display panel operable in a transmissive mode.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an external perspective view of a state of an image displaydevice according to Embodiment 1 when operating in a first transmissivemode.

FIG. 2 is a cross-sectional view of a schematic configuration of adisplay panel and an upper illumination unit according to Embodiment 1.

FIG. 3 is a cross-sectional view of a schematic configuration of thedisplay panel and a lower illumination unit according to Embodiment 1.

FIG. 4 is a side view of the image display device according toEmbodiment 1.

FIG. 5 is an exploded perspective view of a schematic configuration of alower shelf board according to Embodiment 1.

FIG. 6 is an external perspective view of a state of the image displaydevice according to Embodiment 1 when operating in an image displaymode.

FIG. 7 is an external perspective view of a state of the image displaydevice according to Embodiment 1 when operating in a second transmissivemode.

FIG. 8 illustrates a table in which the states of the display panel andthe illumination unit of the image display device according toEmbodiment 1 are summarized for each operation mode.

FIG. 9 illustrates a configuration example of a micro-louver accordingto Embodiment 1.

FIG. 10 illustrates an example of a result of light distribution anglecontrol by the micro-louver illustrated in FIG. 9.

FIG. 11 is an external perspective view of a state of an image displaydevice according to Embodiment 2 when operating in a first transmissivemode.

FIG. 12 is an exploded perspective view of a schematic configuration ofa shelf board according to Embodiment 2.

FIG. 13 is a cross-sectional view of a schematic configuration of adisplay panel and an illumination unit according to Embodiment 2.

FIG. 14 is a side view of the image display device according toEmbodiment 2.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

The inventors of the present application have found the followingproblems in a conventional image display device. As in the conventionaltransparent display, a display panel, which is switchable between astate in which an image is displayed and a transmissive state, forexample, includes: an organic EL panel including a plurality of organicEL elements disposed on a glass substrate; and a light control sheetwhich switches between light transmittance and light non-transmittanceaccording to whether or not voltage is applied to polymer-dispersedliquid crystals.

In such a display panel, for example, by not displaying an image on anorganic EL panel and turning on the light control sheet (making thelight control sheet the transmissive state), it is possible to allow auser in front of the display panel to view objects behind the displaypanel. However, the organic EL panel includes a plurality of organic ELelements arranged in a matrix and the light control sheet includesdispersed liquid crystals. In other words, although the base material ofthe display panel is a transparent material such as a glass, minutelight shielding elements, such as organic EL elements and liquidcrystals, are dispersed in the display panel. Accordingly, for the userwho views the display panel from the front side, the back side of thedisplay panel may look dark. That is, the transmittance of the displaypanel when the display panel operates in a transmissive mode may beinsufficient for viewing of objects behind the display panel. Of course,by placing the image display device in a bright environment, the backside of the image display device also becomes bright. As a result, it ispossible to allow the user to view the objects behind the image displaydevice clearly. However, in this case, when an image is displayed on thedisplay panel, the image may not be viewed properly due to, for example,reflection or transmittance of environmental light on the display panel.

The present disclosure has been conceived based on such finding. As aresult of intensive studies by the inventors of the present application,the inventors have arrived at an idea of a configuration and control ofan image display device which is capable of effectively using a displaypanel which operates in a transmissive mode.

Hereinafter, embodiments will be described with reference to thedrawings as necessary. Note that unnecessarily detailed descriptions maybe omitted. For example, detailed descriptions of already known mattersand overlapping description of substantially the same configuration maybe omitted. This is to avoid the following description to becomeunnecessarily redundant, and to facilitate understanding of the personskilled in the art.

The inventors of the present application provide the accompanyingdrawings and the following description so that the person skilled in theart fully understands the present disclosure, and do not intend to limitthe subject matter of the claims by this.

Moreover, in the following embodiments, the top-bottom direction isrepresented by a Z-axis, the front-back direction is represented by aY-axis, and the left-right direction is represented by an X-axis for thesake of description, but these do not limit the orientation of the imagedisplay device according to the present disclosure at the time ofmanufacture or usage. In the following descriptions, for example, anX-plus axis indicates the direction of the arrow of the X-axis and anX-minus axis indicates the direction opposite of the X-plus axis. Thesame applies to the Y-axis and the Z-axis.

Moreover, in the following embodiments, language such as parallel orperpendicular may be used to indicate the relative orientation of twodirections, but this includes cases where the orientation is not asexactly stated. For example, “two directions are parallel” includessubstantially parallel, that is to say, for example, includes a marginof error of about a few percent, unless otherwise noted, in addition toexactly parallel.

Embodiment 1

Hereinafter, Embodiment 1 will be described with reference to FIG. 1 toFIG. 10. First, with reference to FIG. 1 to FIG. 4, outline of aconfiguration of an image display device according to Embodiment 1 willbe described.

[1-1. Outline of Configuration of Image Display Device]

FIG. 1 is an external perspective view of a state of image displaydevice 10 according to Embodiment 1 when operating in a firsttransmissive mode. FIG. 2 is a cross-sectional view of a schematicconfiguration of display panel 110 and upper illumination unit 220according to Embodiment 1. Specifically, FIG. 2 illustrates across-section taken along line II-II in FIG. 1. FIG. 3 is across-sectional view of a schematic configuration of display panel 110and lower illumination unit 210 according to Embodiment 1. Specifically,FIG. 3 illustrates a portion of a cross-section taken along line III-IIIin FIG. 1. FIG. 4 is a side view of image display device 10 according toEmbodiment 1. In FIG. 4, approximate positions of display panel 110 andlight transmissive panel 300 are indicated by dashed lines anddashed-dotted lines.

As illustrated in FIG. 1 to FIG. 4, image display device 10 according tothe present embodiment includes: image display unit 100 includingdisplay panel 110 and frame 130 supporting display panel 110; shelfboard 150; illumination unit 200; and light transmissive panel 300supported by frame 130.

In the present embodiment, frame 130 includes T frame 131, R frame 132,L frame 133, B frame 134, and M frame 135. T frame 131 is disposed alongthe top side of display panel 110. R frame 132 is disposed along theright side of display panel 110 in the front view. L frame 133 isdisposed along the left side of display panel 110 in the front view. Bframe 134 is disposed along the bottom side of light transmissive panel300. M frame 135 is disposed between display panel 110 and lighttransmissive panel 300. In other words, M frame 135 is disposed across Rframe 132 and L frame 133. Each of these partial frames (131 to 135) ismechanically connected to other adjacent partial frames.

As the material of frame 130, for example, metal such as aluminum oraluminum alloy is used. Accordingly, for example, it is possible toobtain frame 130 with relatively light weight and high strength.Moreover, frame 130 can also function as a heat dissipation member whichdissipates heat generated by illumination unit 200 and the like to theoutside.

With frame 130 having the above configuration, display panel 110 issupposed by T frame 131, R frame 132, L frame 133, and M frame 135.Moreover, light transmissive panel 300 is supported by M frame 135, Rframe 132, L frame 133, and B frame 134. Note that frame 130 is notnecessarily divided into five members as described above. For example,frame 130 may be formed of two members of a rectangular ring-shapedframe corresponding to T, R, L, B frames (131 to 134) and M frame 135.

Display panel 110 is a display device switchable between an imagedisplay mode in which an image is displayed and a transmissive mode inwhich display panel 110 is in a transmissive state where each of objectsbehind image display unit 100 is visible in the front view of displaypanel 110. Specifically, as illustrated in FIG. 2 and FIG. 3, displaypanel 110 includes organic electro-luminescence (EL) panel 111 and lightcontrol panel 112 disposed behind organic EL panel 111. Note that the“image” displayed on display panel 110 may be any of a still image or amoving image, or may be video content including both the still image andthe moving image.

In the present embodiment, organic EL elements, which includes an ELlayer and transparent electrodes sandwiching the EL layer, are disposedin a matrix in organic EL panel 111. The region of organic EL panel 111where an image (including background image) is not displayed has lighttransmitting properties to the extent generally referred to astransparent.

Moreover, light control panel 112 includes light control sheet 113,first glass plate 114 a disposed in front of light control sheet 113,and second glass plate 114 b disposed behind light control sheet 113.Light control sheet 113 is a member switchable between a lighttransmissive state and a light non-transmissive state depending onwhether or not a predetermined voltage is applied to light control sheet113. Light control sheet 113 includes, for example, a liquid crystallayer including liquid crystal molecules having an orientational statechanged by presence or absence of an application of voltage, and resinsheets sandwiching the liquid crystal layer.

Display panel 110, configured such that organic EL panel 111 and lightcontrol panel 112 are layered, becomes, for example, as illustrated inFIG. 1, a transmissive state, in which objects 500 behind image displayunit 100 are visible, by not displaying an image on organic EL panel 111and applying a predetermined voltage to light control sheet 113 (turningon light control sheet 113). In the present embodiment, this operationmode is referred to as a transmissive mode.

More specifically, the case where display panel 110 operates in thetransmissive mode includes a case where an image is not displayed onorganic EL panel 111 as illustrated in FIG. 1 and a case where an imageis displayed on a portion of organic EL panel 111. Accordingly, in orderto distinguish these operation modes from each other, the case where animage is not displayed on organic EL panel 111 as illustrated in FIG. 1is referred to as a first transmissive mode, and the case where an imageis displayed on a portion of organic EL panel 111 is referred to as asecond transmissive mode. The second transmissive mode will be describedlater with reference to FIG. 7. Moreover, display panel 110 may include,for example, an optical element such as an anti-reflection film inaddition to the above structural elements.

Shelf board 150 is disposed on the rear surface of image display unit100 including display panel 110, so as to project rearward. In thepresent embodiment, as illustrated in FIG. 1, shelf board 150 includesupper shelf board 170 and lower shelf board 160. Upper shelf board 170is an example of a first shelf board, and lower shelf board 160 is anexample of a second shelf board. Upper shelf board 170 and lower shelfboard 160 are fixed to frame 130. Moreover, as illustrated in FIG. 1 andFIG. 4, lower shelf board 160 is supported by support member 190 frombelow. Support member 190 houses electric wire 400 electricallyconnected to a controller or the like housed in lower shelf board 160,as will be described later with reference to FIG. 5.

On each of upper shelf board 170 and lower shelf board 160, objects 500(such as a photograph, a doll, a vase, a toy, a model, or a drawing) canbe placed. In the case where display panel 110 operates in the firsttransmissive mode, a user is capable of viewing objects 500 placed onupper shelf board 170 and lower shelf board 160 through display panel110.

In front of lower shelf board 160, M frame 135 is disposed across Rframe 132 and L frame 133. M frame 135 has a pair of openings 135 awhere sound emitted from a pair of loudspeaker devices housed in lowershelf board 160 exits. Although not illustrated, a sheet with the samepattern as lower shelf board 160 (such as wood pattern sheet) is pastedto the front surface of M frame 135, for example. Accordingly, M frame135 is recognized as if it is part of lower shelf board 160 inappearance. Moreover, the sheet has, at positions of openings 135 a, aplurality of minute holes, for example, so as not to prevent emittanceof sound from openings 135 a.

Moreover, M frame 135 also functions to support the upper end of lighttransmissive panel 300. Light transmissive panel 300 is disposed belowdisplay panel 110, and is an example of a plate-shaped lighttransmissive member through which objects placed behind image displayunit 100 are visible. Light transmissive panel 300 is, for example,realized by a glass plate. More specifically, light transmissive panel300 has a light transmittance approximately the same as the lighttransmittance of display panel 110 when operating in the transmissivemode. Moreover, the color of light transmissive panel 300 is alsoadjusted to be close to the color of display panel 110 operating in thetransmissive mode. Accordingly, when display panel 110 is operating inthe transmissive mode, appearance of display panel 110 and lighttransmissive panel 300 is recognized as if it is a continuous glassplate including two tiers of top and bottom shelf boards on the rearsurface.

As described above, display panel 110 includes minute light shieldingelements, such as organic EL elements and liquid crystals, which aredispersedly arranged. Hence, even when display panel 110 operates in thefirst transmissive mode, the light transmittance of display panel 110is, for example, 40% to 50% approximately. Accordingly, for example,when image display device 10 is placed in a relatively dark environment,the user may fail to clearly view objects 500 placed behind displaypanel 110.

However, image display device 10 according to the present embodimentincludes illumination unit 200. Each object 500 placed behind displaypanel 110 can be illuminated with the light emitted from illuminationunit 200.

Specifically, illumination unit 200 according to the present embodimentincludes, as illustrated in FIG. 2 to FIG. 4, upper illumination unit220 and lower illumination unit 210. Upper illumination unit 220 is anexample of a first illumination unit, and lower illumination unit 210 isan example of a second illumination unit.

Upper illumination unit 220 is disposed at the upper end portion of therear surface of image display unit 100. Specifically, as illustrated inFIG. 2, T frame 131 has holding groove 131 a which holds the upper endportion of display panel 110 and illumination groove 131 b to whichupper illumination unit 220 is attached. Upper illumination unit 220includes light source unit 221 which emits light, and micro-louver 225disposed on the light-emitting side of light source unit 221.Micro-louver 225 is an example of an optical element which limits thedistribution angle of light emitted from light source unit 221. Upperillumination unit 220 is embedded in illumination groove 131 b.Accordingly, when display panel 110 is in the transmissive state, thelight emitted from upper illumination unit 220 is not likely to directlyenter the eyes of the user in front of image display device 10.

Light source unit 221 includes substrate 223 long in the X-axisdirection and a plurality of LED elements 222 mounted on substrate 223.Micro-louver 225 is a member disposed along light source unit 221 andlong in the X-axis direction, and has a configuration in which lightshields and light transmitting bodies extended in the X-axis directionare alternately arranged in the short direction of micro-louver 225. Amore specific configuration example of micro-louver 225 will bedescribed later with reference to FIG. 9 and FIG. 10.

Lower illumination unit 210 is disposed at the base portion of uppershelf board 170. Specifically, as illustrated in FIG. 3, attachmentmember 172 for attaching lower illumination unit 210 is disposed on thebottom surface of the end portion of upper shelf board 170 on the frame130 side. Lower illumination unit 210 is fixed to upper shelf board 170via attachment member 172.

Lower illumination unit 210 has a configuration and features common tothose of upper illumination unit 220. In other words, lower illuminationunit 210 includes light source unit 211 which emits light, andmicro-louver 215 disposed on the light-emitting side of light sourceunit 211. Micro-louver 215 is an example of an optical element whichlimits the distribution angle of light emitted from light source unit211.

Light source unit 211 includes substrate 213 long in the X-axisdirection and a plurality of LED elements 212 mounted on substrate 213.Micro-louver 215 is a member disposed along light source unit 211 andlong in the X-axis direction, and has a configuration in which lightshields and light transmitting bodies extended in the X-axis directionare alternately arranged in the short direction of micro-louver 215.

Micro-louver 225 (215) is capable of limiting the distribution angle oflight emitted from LED elements 222 (212) having, for example, a halfdirectivity angle which is 120° approximately, to 60° approximately.Moreover, micro-louver 225 (215) also functions to hide light sourceunit 221 (211) from the outside and to reduce particulate appearance oflight due to the scattering of LED elements 222 (212), for example.

One or more objects 500 placed on shelf board 150 are illuminated byillumination unit 200 configured as above. In other words, asillustrated in FIG. 4, object 500 b placed on upper shelf board 170 isilluminated by the light emitted from upper illumination unit 220, andobject 500 a placed on lower shelf board 160 is illuminated by the lightemitted from lower illumination unit 210.

More specifically, in upper illumination unit 220, the distributionangle of light emitted from light source unit 221 is narrowed bymicro-louver 225. In other words, the light emitted from upperillumination unit 220 is limited by micro-louver 225 so as to fallwithin a predetermined range centered on upper shelf board 170 in theY-axis direction. Accordingly, the amount of light emitted from upperillumination unit 220 and entering display panel 110 is reduced, and,for example, in the front view of display panel 110, the possibilitythat display panel 110 partially looks white due to the light from upperillumination unit 220 is reduced. Moreover, a state where upperillumination unit 220 unnecessarily illuminates the region behind uppershelf board 170 is unlikely to occur.

In a similar manner, with respect to lower illumination unit 210, thedistribution angle of light emitted from light source unit 211 islimited by micro-louver 215. Accordingly, the illuminated range fallswithin a predetermined range centered on lower shelf board 160.Accordingly, the light emitted from lower illumination unit 210 isunlikely to enter display panel 110. Moreover, a state where lowerillumination unit 210 unnecessarily illuminates the region behind lowershelf board 160 is unlikely to occur.

[1-2. Lower Shelf Board]

Next, a configuration of lower shelf board 160 according to the presentembodiment will be described with reference to FIG. 5. FIG. 5 is anexploded perspective view of a schematic configuration of lower shelfboard 160 according to Embodiment 1. Specifically, FIG. 5 illustrateslower shelf board 160 separated into shelf body 161 and placementsurface 162.

In the present embodiment, lower shelf board 160 is an example of aholding member which holds controller 180 in the housed state.Specifically, as illustrated in FIG. 5, controller 180 is housed insidelower shelf board 160. Controller 180 controls operations of displaypanel 110 and illumination unit 200. Controller 180 includes, forexample, one or more circuit substrates 181, and a plurality ofelectronic components 182 mounted on the one or more circuit substrates181. Controller 180 is disposed along bottom surface 161 a of shelf body161 so that controller 180 falls within the thickness (width in theZ-axis direction) of lower shelf board 160. In other words, flatplate-shaped controller 180 is housed in lower shelf board 160 in anupright position relative to the rear surface of image display unit 100,in a similar manner to lower shelf board 160.

Moreover, lower shelf board 160 further houses loudspeaker devices whichemit sound from the front side of image display unit 100. In the presentembodiment, for example, a pair of loudspeaker devices 184 foroutputting 2-channel stereophonic audio are housed inside lower shelfboard 160. In front of the pair of loudspeaker devices 184, as describedabove, there are openings 135 a formed in M frame 135. The sound outputfrom loudspeaker devices 184 is emitted to the front of image displaydevice 10 via openings 135 a. In such a manner, in the presentembodiment, lower shelf board 160 holding controller 180 also functionsas a member which hides controller 180 and loudspeaker devices 184.

Lower shelf board 160 further includes two exhaust fans 189 for coolingthe devices housed inside lower shelf board 160, such as controller 180and loudspeaker devices 184. By driving these two exhaust fans 189, forexample, outside air is introduced into lower shelf board 160 via holesor gaps formed in lower shelf board 160, and cools controller 180,loudspeaker devices 184, and the like, and is discharged to the outsidethrough two exhaust fans 189.

The elements housed in lower shelf board 160 are not limited to devicessuch as controller 180 and loudspeaker devices 184, but, for example, atelevision tuner and an optical disk player not illustrated may behoused.

As described above, lower shelf board 160 holding controller 180 andloudspeaker devices 184 is supported by support member 190 from below.This increases the withstand load of lower shelf board 160. Accordingly,for example, it is possible to increase the number of or weight of theelements (such as controller 180) housed in lower shelf board 160.Moreover, support member 190 houses electric wire 400 electricallyconnected at least to controller 180. Electric wire 400 is, for example,a power cable connected to a commercial power supply, or a signal cableconnected to an external audio visual (AV) apparatus. Support member 190may house a plurality of electric wires 400. In other words, supportmember 190 which supports lower shelf board 160 from below can be used,for example, as a member which hides electric wire 400 for supplyingelectric power and/or various signals to controller 180. Moreover,support member 190 can also be used, for example, as a member whichbundles a plurality of electric wires 400.

[1-3. Operation Example of Image Display Device]

An operation example of image display device 10 configured as above willbe described with reference to FIG. 6 to FIG. 8. FIG. 6 is an externalperspective view of image display device 10 according to Embodiment 1when operating in an image display mode. FIG. 7 is an externalperspective view of image display device 10 according to Embodiment 1when operating in a second transmissive mode. FIG. 8 illustrates a tablein which the states of the display panel and the illumination unit ofimage display device 10 according to Embodiment 1 are summarized foreach operation mode.

Switching of the operation modes between the above described firsttransmissive mode (see FIG. 1), an image display mode and a secondtransmissive mode to be described below, is performed by, for example, adedicated remote controller for operating image display device 10 or ageneral-purpose mobile terminal or based on a control signal from an AVapparatus or the like which supplies image data to image display device10. Moreover, for example, controller 180 of image display device 10 mayswitch the operation mode based on information added to the image data.

As illustrated in FIG. 6, image display device 10 operates in an imagedisplay mode in which image 120 is displayed on display panel 110. Morespecifically, controller 180 displays image 120 on the entire imagedisplay region of organic EL panel 111, and turns off light controlsheet 113 of light control panel 112 (making light control sheet 113 anon-transmissive state). Moreover, controller 180 turns off illuminationunit 200 (upper illumination unit 220 and lower illumination unit 210).Accordingly, entrance of light coming from the rear surface of organicEL panel 111 is shielded by light control sheet 113, and illumination oflight by illumination unit 200 is stopped. As a result, image 120displayed on display panel 110 is displayed clearly without beinginfluenced by the light emitted from the rear side of display panel 110.

The image data corresponding to the image displayed on display panel 110is supplied to controller 180 from the television tuner housed in lowershelf board 160 or the AV apparatus or the like connected to electricwire 400. Controller 180 drives organic EL panel 111 based on thesupplied image data, so that an image is displayed on display panel 110.The supply source of the image data is not particularly limited. Forexample, image data may be read by controller 180 from a hard disk or asemiconductor memory connected to image display device 10. Moreover,controller 180 may obtain image data from a personal computer, a tablet,a smart phone or the like, via wireless communication in accordance witha predetermined standard such as Bluetooth (registered trademark) orWi-Fi (registered trademark).

Moreover, for example, the expression “turns off light control sheet 113when the operation mode is switched” means if light control sheet 113 isoff before switching of the operation mode, light control sheet 113 ismaintained off. The same applies to the expression “turns on lightcontrol sheet 113”, and also applies to on and off of other devices suchas illumination unit 200.

Moreover, as illustrated in FIG. 7, image display device 10 operates ina second transmissive mode in which display panel 110 is in atransmissive state and an image is displayed on display panel 110. Inother words, in the first transmissive mode illustrated with referenceto FIG. 1, an image is not displayed on display panel 110 and the entirescreen is in a transmissive state. In contrast, in the secondtransmissive mode, a portion of display panel 110 is in a transmissivestate, and images (partial images 121) are displayed on the otherportions of image display panel 110.

In the second transmissive mode, controller 180 displays partial images121 on a portion of the image display region of organic EL panel 111,and turns on light control sheet 113 of light control panel 112 (makinglight control sheet 113 a transmissive state). Moreover, controller 180turns on illumination unit 200 (upper illumination unit 220 and lowerillumination unit 210). Accordingly, the user is capable of viewingobjects 500 placed on shelf board 150 through a region of organic ELpanel 111 where no partial image 121 is being displayed. Moreover, atthis time, objects 500 placed on shelf board 150 are illuminated withlight from illumination unit 200. Accordingly, even when image displaydevice 10 is placed in a relatively dark environment, the user iscapable of viewing objects 500 clearly.

Moreover, for example, it is possible to allow the user to view partialimages 121 as well as objects 500 placed on shelf board 150. Hence, forexample, it is possible to provide augmented reality (AR) video to theuser by a combination of objects 500 and partial images 121.

Each of one or more partial images 121 may be any one of a moving imageand a still image. Moreover, even if partial image 121 itself is any ofthe moving image and the still image, the position of partial image 121on display panel 110 may be constant, or may vary.

The image data for displaying one or more partial images 121 on displaypanel 110 is supplied to controller 180 from a television tuner, an AVapparatus, a personal computer, or the like, in a similar manner toimage 120 in the image display mode (see FIG. 6).

As described above, image display device 10 is capable of operating inthe image display mode and the transmissive mode (first transmissivemode and second transmissive mode). The states (operation details) ofdisplay panel 110 and illumination unit 200 in each operation mode aresummarized as in FIG. 8.

In other words, when image display device 10 operates in an imagedisplay mode in which an image is displayed on the entire screen, animage is displayed on organic EL panel 111 (image display is on), lightcontrol sheet 113 is off (not transmissive), and illumination unit 200is also off (turned off). Accordingly, for example, the user is capableof watching normal television broadcast or movies or the like played onan AV apparatus on image display device 10 with an appropriate imagequality.

Moreover, when image display device 10 operates in a first transmissivemode in which an image is not displayed, an image is not displayed onorganic EL panel 111 (image display is off), light control sheet 113 ison (transmissive), and illumination unit 200 is also on (turned on).Accordingly, for example, the user is capable of clearly viewing,through display panel 110, one or more objects 500 placed on shelf board150 of image display device 10.

Moreover, when image display device 10 operates in a second transmissivemode in which an image is displayed only on a portion thereof, an imageis displayed only on a portion of the image display region of organic ELpanel 111 (image display is on), light control sheet 113 is on(transmissive), and illumination unit 200 is also on (turned on).Accordingly, for example, the user is capable of viewing virtual objects(partial images 121 (see FIG. 7) displayed on display panel 110 and oneor more real objects 500 placed on shelf board 150 within the samescreen at the same time.

In this manner, when image display device 10 according to the presentembodiment operates in a transmissive mode (first transmissive mode andsecond transmissive mode) in which light control sheet 113 is in atransmissive state, controller 180 turns on illumination unit 200. Inother words, the transmissive mode is an operation mode in which eachobject 500 behind display panel 110 is visible through at least aportion of display panel 110. In this case, controller 180 causesillumination unit 200 to emit light by turning on illumination unit 200.Accordingly, it is possible to improve the clarity of objects 500 in thefront view of display panel 110 and the clarity of objects 500 placedbehind display panel 110 having a relatively low light transmittance.

[1-4. Configuration Example of Micro-Louver]

Next, with reference to FIG. 9 and FIG. 10, a configuration example of amicro-louver which is an optical element, which limits the distributionangle of light, included in illumination unit 200 according toEmbodiment 1 will be described.

FIG. 9 illustrates a configuration example of micro-louver 225 accordingto Embodiment 1. FIG. 10 illustrates an example of a result of lightdistribution angle control performed by micro-louver 225 illustrated inFIG. 9.

Note that FIG. 9, FIG. 10 and the descriptions thereof focus onmicro-louver 225 included in upper illumination unit 220. However, thecharacteristic matters related to micro-louver 225 may be applied tomicro-louver 215 included in lower illumination unit 210.

Moreover, the dashed and dotted lines in FIG. 9 represents an opticalaxis of light source unit 221. Moreover, FIG. 10 schematicallyillustrates the distribution of light on upper shelf board 170 whenupper illumination unit 220 is on by using shading of dots. Darker dotsmeans brighter. Moreover, FIG. 10 schematically illustrates micro-louver225 and light source unit 221 to represent that micro-louver 225 isdisposed between light source unit 221 and upper shelf board 170, andthe orientations thereof are different from the actual orientations.

As illustrated in FIG. 9, a plurality of light shields 226 inmicro-louver 225 do not have to be arranged at an equal interval in thearrangement direction of light shields 226 (in the short direction ofmicro-louver 225). For example, as illustrated in FIG. 9, a case isassumed where micro-louver 225 is divided into three regions (regions a,b, c) in the short direction. In this case, the number of light shields226 per unit length in the short direction in each of regions a, b, c(density: Da, Db, Dc) may be Db<Da<Dc.

In this case, in the short direction, the amount of light emitted frommicro-louver 225 is increased by arranging light shields 226 roughly inthe central portion of micro-louver 225. In the rear end portion (endportion in the Y-axis plus side) of micro-louver 225, by arranging lightshields 226 densely, the amount of light emitted from micro-louver 225is reduced. In the front end portion (end portion in the Y-axis minusside) of micro-louver 225, by arranging light shields 226 more densely,the amount of light emitted from micro-louver 225 is further reduced.

As a result, the distribution of the amount of light on upper shelfboard 170 illuminated by upper illumination unit 220 is schematicallyrepresented in FIG. 10. In other words, when the regions of upper shelfboard 170 illuminated with light emitted from regions a, b, c ofmicro-louver 225 are represented by A, B, C, respectively, region B isbrightest, and region A is next brightest, and region C is darkest amongregions A, B, C. In other words, from the central portion to the rearend in the depth direction (Y-axis direction) of upper shelf board 170,much light is emitted. Accordingly, for example, objects 500 placed onupper shelf board 170 can be efficiently illuminated. Moreover, theamount of unnecessary light emitted rearward beyond upper shelf board170 is reduced. Moreover, relative to region C which is close to displaypanel 110, relatively less amount of light is emitted from upperillumination unit 220, and thus, the amount of light emitted from upperillumination unit 220 and entering display panel 110 is reduced.Accordingly, for example, the possibility that display panel 110 lookspartially white due to the light from upper illumination unit 220 isreduced.

By adjusting the density of light shields 226 included in micro-louver225 in this way, the distribution of light emitted to upper shelf board170 can be adjusted. The configuration of micro-louver 225 illustratedin FIG. 9 is an example. For example, in addition to or in place ofdensity of light shields 226, by changing the inclination of lightshields 226, the distribution angle or distribution characteristics oflight emitted from upper illumination unit 220 may be adjusted. In otherwords, one or more light shields 226 among light shields 226 included inmicro-louver 225 may be inclined relative to the optical axis of lightsource unit 221. In other words, the distribution angle or distributioncharacteristics of light emitted from upper illumination unit 220 may beadjusted by adjusting the inclination of one or more light shields 226.

[1-5. Advantageous Effects Etc.]

As described above, image display device 10 according to the presentembodiment includes: image display unit 100 including display panel 110;shelf board 150; and illumination unit 200. Display panel 110 isswitchable between an image display mode in which an image is displayedand a transmissive mode in which display panel 110 is in a transmissivestate where objects 500 behind image display unit 100 are visible in thefront view. Shelf board 150 is disposed projecting rearward from therear surface of image display unit 100, and extends in the lateraldirection. Illumination unit 200 is disposed above shelf board 150, andemits light downward.

With this configuration, objects 500 such as a photograph, a doll, or avase, can be placed on shelf board 150. In at least the transmissivemode, objects 500 placed behind image display unit 100 can be showed tothe user in front of image display unit 100. Moreover, since objects 500are illuminated with the light from illumination unit 200, even when thetransmittance of display panel 110 is not high, illumination sufficientto allow objects 500 to be visible can be provided. In this manner,image display device 10 according to the present embodiment is capableof effectively using display panel 110 which operates in thetransmissive mode.

Shelf board 150 extending in the lateral direction can function as abeam reinforcing image display unit 100, for example. Accordingly, forexample, the size of image display device 10 can be increased.

Moreover, in image display device 10 according to the presentembodiment, illumination unit 200 includes a first illumination unit(upper illumination unit 220) fixed to the upper end portion of the rearsurface of image display unit 100.

Specifically, in the present embodiment, upper illumination unit 220 isfixed to T frame 131. Accordingly, for example, in the front view ofimage display device 10, upper illumination unit 220 which does not needto be shown to the user can be hidden in the upper end portion (T frame131) of image display unit 100. Moreover, for example, even when displaypanel 110 is in the transmissive state, since upper illumination unit220 is embedded in T frame 131 (see FIG. 2), the light emitted fromupper illumination unit 220 is not likely to directly enter the eyes ofthe user in front of display panel 110.

Moreover, in image display device 10 according to the presentembodiment, shelf board 150 includes a first shelf board (upper shelfboard 170) and a second shelf board (lower shelf board 160) disposedbelow upper shelf board 170. Illumination unit 200 includes a secondillumination unit (lower illumination unit 210) which is disposed at thebase portion of upper shelf board 170 and which emits light toward lowershelf board 160.

With this configuration, a plurality of objects 500 can be placed on twotiers of top and bottom shelf boards including upper shelf board 170 andlower shelf board 160, and objects 500 can be efficiently illuminated bytwo tiers of top and bottom illumination units including upperillumination unit 220 and lower illumination unit 210.

Moreover, in image display device 10 according to the presentembodiment, illumination unit 200 includes light source unit 221 whichemits light, and an optical element (micro-louver 225) which is disposedon the light-emitting side of light source unit 221 and limits thedistribution angle of the light.

With this configuration, upper illumination unit 220 including lightsource unit 221 is capable of emitting light efficiently toward uppershelf board 170, for example. Specifically, for example, thedistribution angle (half directivity angle) of light from LED elements222 which is approximately 120° can be limited to approximately 60°.Moreover, by using micro-louver 225 including a plurality of lightshields 226 as an optical element which limits the light distributionangle, for example, LED elements 222 are less likely to be viewed fromthe outside. In other words, micro-louver 225 also functions as a memberwhich hides light source unit 221 including LED elements 222 from theoutside. Moreover, when LED elements 222 are turned on, the light fromeach LED element 222 is scattered by light shields 226. As a result, theparticulate appearance of light caused by turning on LED elements 222 isunlikely to occur. In the present embodiment, lower illumination unit210 includes micro-louver 215 which provides the same advantageouseffects as micro-louver 225.

Moreover, image display device 10 according to the present embodimentfurther includes controller 180 which controls operations of displaypanel 110 and illumination unit 200. When controller 180 operatesdisplay panel 110 in a transmissive mode, controller 180 causesillumination unit 200 to emit light. When controller 180 operatesdisplay panel 110 in an image display mode, controller 180 causesillumination unit 200 to stop emitting light.

In this manner, in the present embodiment, on and off of illuminationunit 200 is appropriately switched according to whether or notcontroller 180 causes display panel 110 to be in a transmissive state.In other words, in synchronization with switching from the image displaymode to the transmissive mode, illumination unit 200 is automaticallyswitched from off to on. Hence, for example, a transition from the imagedisplay mode to the transmissive mode is performed smoothly or reliably.

Moreover, in image display device 10 according to the presentembodiment, controller 180 is housed in shelf board 150. Morespecifically, controller 180 is housed inside lower shelf board 160.

Here, each of lower shelf board 160 and upper shelf board 170 formingshelf board 150 is disposed projecting rearward from the rear surface ofimage display unit 100. In other words, when display panel 110 is in thetransmissive state, lower shelf board 160 and upper shelf board 170 areviewed by the user in the orientation along the direction of the eyes ofthe user. Accordingly, the area of each of lower shelf board 160 andupper shelf board 170 entering the field of view of the user isrelatively small. In the present embodiment, controller 180 is housed inlower shelf board 160 disposed in such an orientation which is lesslikely to be noticed. More specifically, controller 180 including, forexample, circuit substrate 181 and a plurality of electric components182 is housed in lower shelf board 160 in such an orientation that thecomponent mounting surface of circuit substrate 181 is parallel to thefront and back direction (Y-axis direction) (in other words, in anupright position relative to the rear surface of image display unit100). Accordingly, controller 180 required for the operation control ofimage display device 10 can be disposed behind image display unit 100operable in a transmissive mode, and can be kept out of sight.

Moreover, in image display device 10 according to the presentembodiment, the transmissive mode includes: a first transmissive mode inwhich display panel 110 is in a transmissive state and an image is notdisplayed on display panel 110; and a second transmissive mode in whichdisplay panel 110 is in a transmissive state and an image (partial image121) is displayed on a portion of display panel 110.

In other words, image display device 10 according to the presentembodiment is capable of operating any one of the first transmissivemode in which the entire image display region on display panel 110 is inthe transmissive state, and the second transmissive mode in which only aportion of the image display region is in the transmissive state.Moreover, both the first transmissive mode and the second transmissivemode are transmissive modes. Hence, in the first transmissive mode andthe second transmissive mode, illumination unit 200 is on (lightillumination state) and each object 500 placed on shelf board 150 isilluminated with the light from illumination unit 200. Moreover, whenimage display device 10 operates in the second transmissive mode, asillustrated in FIG. 7, it is possible to show virtual objects (partialimages 121) and real objects 500 on the same screen to the user at thesame time. In other words, image display device 10 is capable ofproviding AR video which uses one or more objects 500 placed on shelfboard 150 to the user.

Partial images 121 each may be numbers, letters, symbols, or anycombination thereof for providing some kind of information, such as timedisplay, to the user.

Embodiment 2

Next, with reference to FIG. 11 to FIG. 14, image display device 10 aaccording to Embodiment 2 will be described. In the followingdescription, descriptions of the structural elements and operationdetails common to those in Embodiment 1 are appropriately omitted, andthe differences from Embodiment 1 will be mainly described.

FIG. 11 is an external perspective view of image display device 10 aaccording to Embodiment 2 when operating in a first transmissive mode.FIG. 12 is an exploded perspective view of a schematic configuration ofshelf board 250 according to Embodiment 2. Specifically, FIG. 12illustrates shelf board 250 separated into shelf body 251 and placementsurface 252.

FIG. 13 is a cross-sectional view of a schematic configuration ofdisplay panel 110 and illumination unit 201 according to Embodiment 2.Specifically, FIG. 13 illustrates a portion of a cross-section takenalong line XIII-XIII in FIG. 11. FIG. 14 is a side view of image displaydevice 10 a according to Embodiment 2. In FIG. 14, illustration ofright-side wall 232 is omitted, and the side surfaces of display panel110 and illumination unit 201 are simply illustrated.

As illustrated in FIG. 11 to FIG. 14, image display device 10 aaccording to the present embodiment includes: image display unit 101including display panel 110; shelf board 150; frame 230; andillumination unit 201. In the present embodiment, image display unit 101is surrounded, from the outer periphery, and supported by an enclosuremember including frame 230 and shelf board 250 and having a rectangularring shape. Moreover, in the present embodiment, image display unit 101may include members other than display panel 110, such as a protectivepanel for protecting the front face of display panel 110, however, thedescriptions and illustrations thereof are omitted.

As described in Embodiment 1, display panel 110 is a display deviceswitchable between an image display mode in which an image is displayedand a transmissive mode in which display panel 110 is a transmissivestate where objects behind display panel 110 are visible in the frontview. As illustrated in FIG. 12, display panel 110 includes organic ELpanel 111, and light control panel 112 disposed behind organic EL panel111. In FIG. 11, display panel 110 is operating in the firsttransmissive mode, and objects 500 behind display panel 110 are visiblefrom the front side of display panel 110. Moreover, although notillustrated, display panel 110 is also capable of operating in the imagedisplay mode (see FIG. 6) and the second transmissive mode (see FIG. 7),and such features of display panel 110 are common between Embodiments 1and 2.

In the present embodiment, frame 230 includes top wall 231, right-sidewall 232, and left-side wall 233. Top wall 231 is disposed along the topside of image display unit 101. Right-side wall 232 is disposed alongthe right side of image display unit 101 in the front view. Left-sidewall 233 is disposed along the left side of image display unit 101 inthe front view. Right-side wall 232 is connected to the right endportion of shelf board 250 in the front view, and left-side wall 233 isconnected to the left end portion of shelf board 250 in the front view.Top wall 231 is connected to the upper end portions of right-side wall232 and left-side wall 233. Top wall 231 and shelf board 250 andright-side wall 232 and left-side wall 233 are connected by, forexample, screws. In the present embodiment, shelf board 250 is treatedas a separate member from frame 230. However, shelf board 250 may betreated as part of frame 230.

As illustrated in FIG. 11 and FIG. 12, left-side wall 233 has holdinggroove 233 a for holding the left edge of image display unit 101 in thefront view. In a similar manner, right-side wall 232 has a holdinggroove (not illustrated) for holding the right edge of image displayunit 101 in the front view. As illustrated in FIG. 12 to FIG. 14, topwall 231 has holding groove 231 a for holding the upper edge of imagedisplay unit 101.

In the present embodiment, each of top wall 231, right-side wall 232,and left-side wall 233 is made of wood. Accordingly, while image displaydevice 10 a is operating in the first transmissive mode as illustratedin FIG. 11, image display device 10 a is recognized as furniture ordisplay furniture for displaying objects 500 with the front face coveredwith a glass.

Shelf board 250 is disposed projecting rearward from the rear surface ofimage display unit 101. Specifically, as illustrated in FIG. 11, FIG.12, and FIG. 14, shelf board 250 has, at the front end portion, support255 which supports the lower edge of image display unit 101. Shelf board250 has a portion which projects rearward from the rear surface of imagedisplay unit 101 beyond support 255. Shelf board 250 extends in thelateral direction (left-right direction). Shelf board 250 has a sizewhich supports and covers the entire lower side of image display unit101.

Objects 500 are placed on placement surface 252 forming the upper faceof shelf board 250. Objects 500 are viewed by a user in front of imagedisplay device 10 a through display panel 110 operating in the firsttransmissive mode or the second transmissive mode. The transmittance ofdisplay panel 110 is, for example, approximately 40% to 50%. Hence, whenimage display device 10 a is placed in a relatively dark environment,the user may fail to clearly view objects 500. In a similar manner toimage display device 10 according to Embodiment 1, image display device10 a includes illumination unit 201 which emits illumination light toobjects 500.

Illumination unit 201 is disposed at the upper end portion of the rearsurface of image display unit 101. Specifically, as illustrated in FIG.13, top wall 231 has illumination groove 231 b for attachingillumination unit 201. Illumination unit 201 includes light source unit202 which emits light and heat sink 205 for dissipating heat generatedby light source unit 202. Heat sink 205 also functions as an attachmentmember for attaching light source unit 202 to illumination groove 231 b.Heat sink 205 is a metal member such as aluminum or aluminum alloy.Light source unit 202 includes substrate 204 long in the X-axisdirection and a plurality of LED elements 203 mounted on substrate 204.In a similar manner to illumination unit 200 according to Embodiment 1,on and off of illumination unit 201 are switched in synchronization withthe switching of display panel 110 between the transmissive state andthe non-transmissive state (for example, see FIG. 8). Accordingly, forexample, as illustrated in FIG. 14, objects 500 located belowillumination unit 201 are illuminated so that the user is capable ofviewing objects 500 more clearly through display panel 110. Moreover,illumination unit 201 is embedded in illumination groove 231 b.Accordingly, when display panel 110 is turned into a transmissive state,the light emitted from illumination unit 201 is not likely to directlyenter the eyes of the user in front of image display device 10 a.

Although not illustrated in FIG. 13, illumination unit 201 according tothe present embodiment may include a micro-louver which is an opticalelement which limits the distribution angle of the light from lightsource unit 202. Accordingly, it is possible to efficiently emit lightfrom light source unit 202 to objects 500. Moreover, the amount of lightentering display panel 110 from illumination unit 201 is reduced. Thisreduces, for example, the possibility that display panel 110 partiallylooks white due to light from illumination unit 201.

In image display device 10 a configured as above, the operations ofdisplay panel 110 and illumination unit 201 included in image displayunit 101 are controlled by controller 180 held in shelf board 250. Shelfboard 250 is an example of a holding member which holds controller 180in the housed state. Specifically, controller 180 is housed inside shelfboard 250 as illustrated in FIG. 12. Controller 180 is disposed alongbottom surface 251 a of shelf body 251 so that controller 180 fallswithin the thickness (width in the Z-axis direction) of shelf board 250.In other words, flat plate-shaped controller 180 is housed in shelfboard 250 in an upright position relative to the rear surface of imagedisplay unit 101 in a similar manner to shelf board 250.

Although not illustrated in FIG. 12, shelf board 250 may houseelectronic devices such as loudspeaker devices and exhaust fans, in asimilar manner to lower shelf board 160 according to Embodiment 1.

As described above, image display device 10 a according to the presentembodiment includes: image display unit 101 including display panel 110;shelf board 250; and illumination unit 201. Display panel 110 isswitchable between an image display mode in which an image is displayedand a transmissive mode in which image display unit 100 is in atransmissive state where objects 500 behind image display unit 100 arevisible in the front view. Shelf board 250 is disposed projectingrearward from the rear surface of image display unit 101, and extends inthe lateral direction. Illumination unit 201 is disposed above shelfboard 250 to emit light downward.

With this configuration, objects 500, such as a photograph, a doll, or avase, can be placed on shelf board 250. In at least the transmissivemode, objects 500 placed behind image display unit 100 can be displayedto the user in front of image display unit 100. Moreover, since objects500 are illuminated with light from illumination unit 201, even when thetransmittance of display panel 110 is not high, illumination sufficientto allow objects 500 to be visible can be provided. As described, imagedisplay device 10 a according to the present embodiment is capable ofeffectively using display panel 110 operating in the transmissive mode.

Moreover, image display device 10 a according to the present embodimentfurther includes, in the front view, right-side wall 232 connected tothe right end portion of shelf board 250 and covering image display unit101 from the right side; left-side wall 233, in the front view,connected to the left end portion of shelf board 250 and covering imagedisplay unit 101 from the left side; and top wall 231 connected to theupper end portions of right-side wall 232 and left-side wall 233 andcovering image display unit 101 from above.

In this manner, in the present embodiment, image display unit 101 issurrounded by an enclosure member including frame 230 and shelf board250 and having a rectangular ring shape. As a result, image displaydevice 10 a has a simple box shape as a whole. Moreover, shelf board 250forming the bottom face of image display device 10 a has a relativelylarge area in a plan view. Weights of controller 180, objects 500, andthe like are applied downward to shelf board 250. Hence, shelf board 250can be used as a stand for image display device 10 a, and for example,image display device 10 a can be placed on the floor surface in a house.Moreover, as described above, for example, frame 230 can be made ofwood. This allows image display device 10 a to look like furniture ordisplay furniture for displaying objects 500 in a room.

Other Embodiments

As described above, embodiments have been described as examples of thetechnique disclosed in the present application. However, the techniqueaccording to the present disclosure is not limited to these examples,and is applicable to embodiments to which various kinds ofmodifications, replacements, additions, deletions have appropriatelybeen made. Moreover, each structural element described above may becombined to obtain a new embodiment. Another embodiment will bedescribed below as an example.

For example, display panel 110 according to an embodiment may include adifferent type of display device from organic EL panel 111, as a displaydevice for displaying an image. Specifically, instead of organic ELpanel 111, an inorganic EL panel which is a self-emitting display devicelike organic EL panel 111 may be included in display panel 110.

Moreover, the second transmissive mode may be treated as one type of“image display mode” because it is an operation mode in which an imageis displayed in a portion of display panel 110. For example, it may bethat the operation mode of image display device 10 illustrated in FIG. 6is a “first image display mode”, and the operation mode of image displaydevice 10 illustrated in FIG. 7 may be a “second image display mode”. Inthis case, when display panel 110 operates in the image display mode,controller 180 basically causes illumination unit 200 to stop emittinglight, and as an exception, causes illumination unit 200 to emit lightwhen display panel 110 operates in the second image display mode.Accordingly, in the same manner as the case where display panel 110operates in the second transmissive mode, it is possible to allow theuser to clearly view objects 500 behind display panel 110 through aportion of display panel 110 where partial images 121 are displayed.

Moreover, shelf board 150 does not always have to include two shelfboards (upper shelf board 170 and lower shelf board 160) disposed awayfrom each other in the vertical direction. For example, shelf board 150may only include lower shelf board 160. In other words, only lower shelfboard 160 may be treated as shelf board 150.

Moreover, shelf board 150 may include three or more shelf boardsseparated from each other in the vertical or lateral direction. In anycase, it is sufficient that illumination unit 200 is disposed so as toilluminate objects 500 placed on each of one or more shelf boardsincluded in shelf board 150. In other words, illumination unit 200 doesnot always have to include two illumination units (upper illuminationunit 220 and lower illumination unit 210) disposed away from each otherin the vertical direction. It is sufficient that illumination unit 200includes one or more illumination units so as to emit light toward eachof the shelf boards included in shelf board 150 and physically separatedfrom each other.

Moreover, the optical element which is included in upper illuminationunit 220 and which limits the distribution angle of light from lightsource unit 221 may be a different type of optical element (such as lensor reflective plate) from the micro-louver. In a similar manner to lowerillumination unit 210, for example, a lens or a reflective plate may beused as an optical element.

Moreover, for example, a third illumination unit may be disposed at thebase portion of lower shelf board 160 (at the end closer to lighttransmissive panel 300) such that the optical axis is directeddiagonally downward. Accordingly, for example, objects 500 placed behindlight transmissive panel 300 can be illuminated by the thirdillumination unit. In this case, a shelf board for placing objects 500(third shelf board) may be disposed behind light transmissive panel 300.In this case, for example, in synchronization with switching of displaypanel 110 between the transmissive state and the non-transmissive state,on and off of the third illumination unit may be switched. Moreover, thethird illumination unit may be always on when the main power of imagedisplay device 10 is on.

Moreover, it has been described that light control sheet 113 accordingto Embodiments 1 and 2 can be switched from the non-transmissive stateto the transmissive state by an application of a predetermined voltage(by turning on light control sheet 113). However, light control sheet113 may be switched from the transmissive state to the non-transmissivestate by an application of a predetermined voltage. In this case, forexample, even when the main power of image display device 10 is off,light control sheet 113 is maintained in the transmissive state.Accordingly, even when the main power of image display device 10 is off,it is possible to allow the user in front of display panel 110 to viewobjects 500 placed behind display panel 110 through display panel 110.In this case, in order to illuminate objects 500, image display device10 may include an electric circuit which is capable of turning onillumination unit 200 (causing illumination unit 200 to illuminate) evenwhen the main power of image display device 10 is off.

Moreover, the material of frame 130 does not have to be metal such asaluminum or aluminum alloy. For example, resin may be used as thematerial of frame 130.

Moreover, in Embodiment 1, a holding member for holding controller 180is lower shelf board 160. However, the holding member for holdingcontroller 180 does not have to be a shelf board on which one or moreobjects 500 can be placed. For example, controller 180 may be held in aflat plate shaped case disposed projecting rearward from the rearsurface of image display unit 100. In this case, the case may have ashape, an orientation, a size or a strength which does not allow one ormore objects 500 to be placed on the case or which is unsuitable forsuch a placement. Even in this case, since the case is disposedprojecting rearward from the rear surface of image display unit 100, thecase has an orientation which is less likely to be noticed in the frontview of display panel 110 operating in the transmissive mode.Accordingly, controller 180 required for the operation control of imagedisplay device 10 can be disposed behind image display unit 100 operablein the transmissive mode, and can be kept out of sight.

Moreover, display panel 110 does not have to include light control panel112. In this case, in the image display mode, clarity of the displayedimage may be reduced because light control panel 112 does not shieldentrance of light from the rear surface of organic EL panel 111.However, in the first transmissive mode and the second transmissivemode, loss of the light transmittance by light control panel 112 iseliminated, and thus, clarity of objects 500 when viewed through displaypanel 110 is improved.

Moreover, the supplementary notes related to Embodiment 1 describedabove may be applied to Embodiment 2. For example, right-side wall 232or left-side wall 233 instead of shelf board 250 may function as aholding member for holding controller 180. In this case, a connectorwhich makes connection with an external device can be disposed in arelatively large area in the right surface or the left surface of imagedisplay device 10 a.

Moreover, for example, image display device 10 a according to Embodiment2 may include a plurality of shelf boards disposed separately from eachother in the vertical direction. For example, in image display device 10a, shelf board 250 may include a lower shelf board disposed at theposition of current shelf board 250, and an upper shelf board disposedbetween the lower shelf board and top wall 231. In this case, in asimilar manner to illumination unit 200 according to Embodiment 1,illumination unit 201 may include an upper illumination unit forilluminating objects 500 placed on the upper shelf board and a lowerillumination unit for illuminating objects 500 placed on the lower shelfboard. Moreover, in this case, one of the lower shelf board and theupper shelf board may hold controller 180.

Moreover, frame 230 according to Embodiment 2 does not have to be madeof wood. For example, at least a portion of each of top wall 231,right-side wall 232, and left-side wall 233 may be made of resin ormetal.

Moreover, image display device 10 a according to Embodiment 2 mayinclude a stand or the like for placing image display device 10 a belowshelf board 250. The placement of image display device 10 a is notparticularly limited. For example, image display device 10 a may beattached to the wall surface by, for example, a wall hanging unit.

Moreover, image display unit 101 may be placed in one section of a rackhaving a plurality of sections arranged in the vertical or lateraldirection where objects 500 can be placed. Accordingly, it is possibleto configure an image display device (or a rack) such that exhibition ofobjects 500 and display of an image can be performed in at least onesection, and objects 500 can be exhibited or housed by using another oneor more sections.

Moreover, objects 500 do not always have to be placed on shelf boards150 and 250. Shelf board 150 may function only as a portion of thebuilding frame of image display device 10, and shelf board 250 mayfunction only as a portion of the building frame of image display device10 a. Moreover, illumination units 200 and 201 may be used not forilluminating objects 500 below, but for illuminating a space where imagedisplay device 10 or 10 a is placed (indirect lighting)

Moreover, in image display devices 10 and 10 a, controller 180 may bedisposed outside image display devices 10 and 10 a. For example, inorder to reduce the thickness of lower shelf board 160, an electronicdevice, such as controller 180, may be housed in a housing separate fromimage display device 10. In order to reduce the thickness of shelf board250, an electronic device, such as controller 180, may be housed in ahousing separate from image display device 10 a.

As described above, embodiments have been described as examples of thetechnique disclosed in the present disclosure. For this purpose, theaccompanying drawings and detailed description are provided.

Accordingly, the structural elements described in the accompanyingdrawings and detailed description may include not only structuralelements which are essential for solving the problem but also structuralelements which are not essential for solving the problem but areprovided for illustrating the technique. Therefore, the non-essentialstructural elements described in the accompanying drawings and/or thedetailed description should not be instantly acknowledged to beessential structural elements.

Since the above embodiments are intended to illustrate the technique inthe present disclosure, it is possible to make various kinds ofmodifications, replacements, additions, deletions, and the like withinthe scope of the claims or an equivalent scope thereof.

INDUSTRIAL APPLICABILITY

The present disclosure is applicable to an image display device, such asa television receiver, a monitor display, or a digital signage.

REFERENCE MARKS IN THE DRAWINGS

-   -   10, 10 a image display device    -   100, 101 image display unit    -   110 display panel    -   111 organic EL panel    -   112 light control panel    -   113 light control sheet    -   114 a first glass plate    -   114 b second glass plate    -   120 image    -   121 partial image    -   130 frame    -   131 T frame    -   131 a, 231 a, 233 a holding groove    -   131 b, 231 b illumination groove    -   132 R frame    -   133 L frame    -   134 B frame    -   135 M frame    -   135 a opening    -   150, 250 shelf board    -   160 lower shelf board    -   161, 251 shelf body    -   161 a, 251 a bottom surface    -   162, 252 placement surface    -   170 upper shelf board    -   172 attachment member    -   180 controller    -   181 circuit substrate    -   182 electronic component    -   184 loudspeaker device    -   189 exhaust fan    -   190 support member    -   200, 201 illumination unit    -   210 lower illumination unit    -   202, 211, 221 light source unit    -   203, 212, 222 LED element    -   204, 213, 223 substrate    -   205 heat sink    -   215, 225 micro-louver    -   220 upper illumination unit    -   226 light shield    -   230 frame    -   231 top wall    -   232 right-side wall    -   233 left-side wall    -   255 support    -   300 light transmissive panel    -   400 electric wire    -   500, 500 a, 500 b object

1. An image display device, comprising: an image display unit whichincludes a display panel switchable between an image display mode and atransmissive mode, the image display mode being a mode in which an imageis displayed, the transmissive mode being a mode in which the displaypanel is in a transmissive state where an object behind the imagedisplay unit is visible in a front view of the display panel; a shelfboard which is disposed projecting rearward from a rear surface of theimage display unit, the shelf board extending in a lateral direction;and an illumination unit which is disposed above the shelf board andemits light downward.
 2. The image display device according to claim 1,wherein the illumination unit includes a first illumination unit fixedto an upper end portion of the rear surface of the image display unit.3. The image display device according to claim 1, wherein the shelfboard includes a first shelf board and a second shelf board disposedbelow the first shelf board, and the illumination unit includes a secondillumination unit disposed at a base portion of the first shelf board,the second illumination unit emitting light toward the second shelfboard.
 4. The image display device according to claim 1, wherein theillumination unit includes: a light source unit which emits light; andan optical element which is disposed on a light-emitting side of thelight source unit and limits a distribution angle of the light.
 5. Theimage display device according to claim 1, further comprising: acontroller which controls an operation of the display panel and anoperation of the illumination unit, wherein the controller causes theillumination unit to emit light when the controller causes the displaypanel to operate in the transmissive mode, and causes the illuminationunit to stop emitting light when the controller causes the display panelto operate in the image display mode.
 6. The image display deviceaccording to claim 5, wherein the controller is housed in the shelfboard.
 7. The image display device according to claim 1, wherein thetransmissive mode includes a first transmissive mode and a secondtransmissive mode, the first transmissive mode being a mode in which thedisplay panel is in the transmissive state and the image is notdisplayed on the display panel, the second transmissive mode being amode in which the display panel is in the transmissive state and theimage is displayed only on a portion of the display panel.
 8. The imagedisplay device according to claim 1, further comprising: a right-sidewall connected to a right end portion of the shelf board and coveringthe image display unit from a right side, in the front view; a left-sidewall connected to a left end portion of the shelf board and covering theimage display unit from a left side, in the front view; and a top wallconnected to an upper end portion of each of the right-side wall and theleft-side wall, and covering the image display unit from above.